Sheet post-handling device

Abstract

A sheet post-handling device made compact by incorporating a stapling unit within a first side frame and a sheet transferring system in a second side frame. A simple mechanism formed of only one driving motor and a transmission means with sheet transmission rollers and a timing gear wheel operated with exquisite timing enables the sheet transferring system to be rationally assembled within the second side frame. With the sheet transferring system, a sheet fed from an image forming apparatus such as a copying machine is transferred in the forward direction, and then, sent back onto a processing tray in the reverse direction. A plurality of sheets sent onto and stacked on the processing tray are stapled, and thereafter, sent out in the forward direction. The stapling unit is movably mounted on the first side frame to facilitate fitting and removal of the staple cartridge into and from the stapling unit and maintenance of the device.

What is claimed is:  
     
       1. A sheet post-handling device comprising a sheet transfer passage extending from a sheet reception part to a sheet discharge part, first and second side frames on both sides of said sheet transfer passage, a sheet processing tray defined between said side frames for supporting a part of sheets to be processed, a stapling unit mounted in said first side frame for stapling the sheets at one side portion of said sheet processig tray, a sheet transferring system for transferring the sheet along said sheet transfer passage, and a driving system for driving the sheet transferring system, sad driving system being mounted in said second side frame. 
     
     
       2. The sheet post-handling device as claimed in  claim 1 , further comprising a sheet aligning member for aligning the sheets on said sheet processing tray by pressing the sheets against said first side frame. 
     
     
       3. The sheet post-handling device as claimed in  claim 1 , wherein said sheet transferring system includes sheet introducing rollers disposed at said sheet reception part, feeding rollers disposed on said sheet transfer passage, a large diameter feeding ring having its upper portion coming in contact with said feeding rollers so as to rotate in conjunction with said feeding rollers and its lower portion coming in elastic contact with said sheet processing tray, and sheet discharge rollers disposed at said sheet disharge part, and wherein said driving system includes one motor for rotating at least one of said sheet introducing rollers and at least one of said discharge rollers, a timing gear wheel selectively driven by said feeding rollers, and a paddle disposed at the sheet discharge part to be selectively driven to rotate. 
     
     
       4. The sheet post-handling device as claimed in  claim 3 , wherein said timing gear wheel selectively imparts rotation to one of said sheet discharge rollers through at least one gear. 
     
     
       5. The sheet post-handling device as claimed in  claim 3 , wherein at least one of said sheet introducing rollers selectively imparts rotation to at least one of said sheet discharge rollers through a transmission means incorporated within said first side frame. 
     
     
       6. The sheet post-handling device as claimed in  claim 3 , wherein one of said sheet discharge rollers is supported by a rocking arm so as to be selectively brought into contact with the other sheet discharge rollers. 
     
     
       7. The sheet post-handling device as claimed in  claim 1 , wherein said stapling unit includes a staple cartridge detachably fitted into said stapling unit, and a lid cover hinged openably on said first side frame. 
     
     
       8. The sheet post-handing device as claimed in  claim 7 , wherein said lid cover is provided with a guide for introducing said staple cartridge into said stapling unit. 
     
     
       9. The sheet post-handling device as claimed in  claim 7 , wherein said stapling unit is held by a bracket rotatably supported on said first side frame. 
     
     
       10. A sheet post-handling device comprising: 
       a sheet transfer passage extending from a sheet reception part to a sheet discharge part,  
       first and second side frames formed on both sides of said sheet transfer passage,  
       a sheet processing tray defined between said side frames for supporting a tail end part of sheets to be processed,  
       a stapling unit mounted in said first side frame for stapling the sheets at one side portion of said sheet processing tray,  
       a sheet transferring system including sheet introducing rollers disposed at said sheet reception part, feeding rollers disposed on said sheet transfer passage, a large diameter feeding ring rotatable in conjunction with said feeding rollers, and sheet dissharge rollers disposed at said sheet discharge part, and  
       a driving system incorporated within said second frame, said driving system including one motor for rotating said sheet introducing rollers and said feeding rollers in a forward direction, a timing gear wheel selectively driven by said feeding rollers, a paddle disposed at the sheet discharge part to be selectively driven to rotate, and a transmission means for selectively transmitting rotation of said timing gear wheel to said discharge rollers.